Performance of neutron polarimeter SMART-NPOL

The neutron polarimeter SMART-NPOL has been constructed at the RIKEN Accelerator Research Facility for measuring polarization correlations of proton-neutron systems. The SMART-NPOL system consists of 12 parallel neutron counter planes of two dimensionally position-sensitive plastic scintillators with a size of 60 x 60 x 3.0 cm(3). Polarimetry measurements were made using the analyzing power of the H-1((n) over right arrow ,n)H-1 reaction occurring in the plastic scintillators. The effective analyzing power of SMART-NPOL was measured with polarized neutrons from the zero-degree Li-6((d) over right arrow, (n) over right arrow) reaction with an incident deuteron energy of 135 MeV/A. The effective analyzing power thus obtained was 0.26 +/- 0.01(stat) +/- 0.03(syst) and the double scattering efficiency was 1.1 x 10(-3). (c) 2007 Elsevier B.V. All rights reserved.